Boiler



G. L. WELLER April 17, 192s.

BOILER Filed April 16. 1927 foecf WELLER Z4;

Patented Apr. 17, 1928.l

UNITED STATES 1,666,276 PATENT omer..

GEORGE L. wELLER, F ELYRIA, OHIO, ASSIGNOR TO NATIONAL TUBE COMPANY, A

CORPORATION OF NEW JERSEY.

BOILER.

Application filed April 16, 1927. Serial No. 184,329.

This invention relates to boilers and more particularly to waste-heatboilers and has for one of its objects the provision of a boilerconstruction which will utilize the maxi- `mum amount of heat from thegases passing therefrom.

Another object is to provide a boiler which will give a maximum andsteadyrsupply of dry steam.

A further object is to provide a boiler 1n which the scale deposit willbe reduced to a minimum, thereby resulting in higher etticiency.

In the drawings- Y The figure shows a vertical section through a boilerconstructed-in accordance with this invention.

Referring more particularly to the drawings, the letters A, B, and Cdeslgnate the banks-of boiler tubes which are supported in the heatingchamber 2. The banks of tubes A and B are inclined from front to back ofthe chamber 2 and are connected at` the front and back ends by the usualtube headers'3 and 4, respectively. combined expansion and steam drum 51s mounted above the rear end of the upper bank of tubes A at a levelabove the highest point of the bank of tubes A and is connected to thetube headers 3 and 4 by tubes or pipes 6 and 7, respectively, so as toprovide for circulation through the tubes to and from said drum. Amanifold drum 8 is also mounted below and connected with the headers 3.

The heating chamber 2 is divided intermef diate the front and back wallsof the boiler structure by a vertically disposed b afe wall 9, intoprimary'and secondary heatmg zones X and Y. respectively.

The primary heating zone X has lts lower end closed by a wall 10 whilethe secondary heating zone has its lower end open and 1n communicationwith an outlet passageway 12 forthe waste-heat gases, which passagewaycommunicates with a stack flue 13 through which the gases are drawn bythel stack draft or by an induced draft fan (not shown) as desired.

`The bank of tubes C are disposed in the outlet passageway 12 and 'areinclined from y back to front of the passagewayjand have their front andback ends connected. by the usual tube headers 14 and 15, respectwely.The headers 15 are connected with the headers 4 so as to provide forpassage of the water and steam from the tubes of the bank C with thebanks A and B.

The headers 14 are connected at their lower end with a feedwater andblow-off drum 16, which is connected to a feedwater line (not shown) andhas blow-off tubes 17 which connect with a pipe 18 leading to a blow-0Event (not shown).

. A waste-heat ue 19 opens through a port 20 into the lowerend of theprimary heating zone X d The waste-heat gases enter. the zone X of thechamber 2 and, due to the baille wall 9,

are compelled to pass upwardly around the .front half of the banks oftubes A and B and then downwardly around the rear half of the banks oftubes A and B in the zone Y. The gases then enter the outlet passagewayBy admitting the feedwater to the lower l end of the bank of tubes C asabove described, the scale deposit in the tubes is held to a minimumsince the feedwater is heated in the bank of tubes C to a point wherethe scale forming solids are precipitated in the tubes C where thetemperature is low enough to prevent adhering to the tubes and iscarried away through the blow-oft1 tubes 17.

' While I have shown and described one speciiic embodiment of myinvention it will be understood that I do not'wish to be limited theretosince various modifications may be made without departing from the scopeof my invention, as defined in the appended claim.

I claim- A waste-heat boiler comprising a heating chamber, a pluralityof banks of tubes inclined from front to back of said chamber, tubeheaders connecting the tubes of said vbanks at each end,-an expansionand Steam drum above said banks of tubes,mea ns connecting said headerswith said expanslon and steam drum, a baffle wall extending verticallyin said heating chamber ,intermediate the front and back walls ofsaidchamber s0 as togdivide said lchamber into primary and secondaryheating zones, an inlet for the waste-heat gases communicating with saidprimary heating zone, an outlet pas-` necting the rear ends of the tubesof said first named banks of tubes, other tube headers connecting theforward ends of the tubes` of said last named bank of tubes, a combinedfeedwater and blow-off drum communicating with all of the tubelieadersconnecting the yforward ends of the tubes of said last named bank oftubes, and a stack flue communicating with said Outlet passageway belowthe forward end of said last bank of tubes.

In testimony whereof, I have hereunto y signed my name.

GEORGE L. VVELLER.

